Machine for cutting and trimming sheet-metal strips.



R. HELMOLD & H. LORCH. MACHINE FOR CUTTING ANDTRIMMING SHEET METAL STRIPS.

APPLICATION FILED MAY l- I916.

Patented June 11, 1918.

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RICHARD HELIVIOLD AND HENRY LOROI-I, OF CHICAGO, ILLINOIS, ASSIGNORS TO J. F. HELMOLD & 3330., OF CHICAGO, ILLINOIS, A COPA-RTNERSI-IIP.

MACHINE FOB, CUTTING AND TRIIVIMING SHEET-METAL STRIPS.

Specification of Letters Patent. Patented June 11, 1918.

Application filed May 1, 1916. Serial No. 94,665.

To all whom it may concern:

Be it known that we, RICHARD HnLMoLn and HENRY LORCII, citizens of the United States, residing in Chicago, in the county of Cook and State of Illinois, have invented certain new anduseful Improvements in Machines for Cutting and Trimming Sheet- Wetal Strips, of which the following is a specification.

Strips ofsheet metal are frequently bent to a large variety of curves or angles and used for an equally large number of purposes. In many instances exactness in length is essential and it is found impracticable, in many instances, to cut the strip of metal, while still in the flat, to the exact length necessary and afterward bend it to the desired shape, bringing the ends exactly to the positions that they should occupy. The

principal object of the present invention is to provide a machine by which a bent strip may be cut or trimmed on any desired line in order to carry out the scheme of the device in hand, but a machine embodying the invention may with equal facility be used for cutting straight flat strips into exact lengths.

To these ends the invention consists in the features of novelty that are hereinafter described with reference to the accompanying drawingwhich is made a part of this specification and in which:

Figure I is an elevation of a machine embodying the invention.

Fig. II is a plan view thereof.

Fig. III is a vertical transverse section thereof on the line IIIIII, Fig. II, viewed in the direction of the arrow.

Fig. IV is a detail viewed in the direction of the arrow IV, Fig. II.

The improved machine has a bed-plate, 1, of truncated, inverted V-shape the diverging downwardly extending ends or legs 2, of which have flanges, 3, provided with perforations, a, for the passage of screws or the like by which the bed-plate may be secured to a work-bench, table, or other suitable support. For the purpose of giving it the necessary strength the bedplate has, formed integrally with it, a downwardly extending vertical flange, 5, the ends of which join the downwardly extending ends, or legs, 2. Preferably the parts thus far described, and also a post 5, rising from the bed plate near one of its ends are an integral casting of edge of the wear-plate, 6, and in part by the vertical SlClC of a flange, 10, whlch rises from the bed-plate, 1, and in part also by agroove of substantially v shape which is formed in the lower slde of a clamping-plate, 11, which is secured by screws, 12, to the top side ofv the flange, 10.

As shown in Fig. II the openings, 13, through which the screws, 12, pass are clongated and as shown in Fig. I V, the meeting faces of the flange, 10, and clamping plate, 11, are inclined, sloped or beveled, whereby the clamping plate, 11, may be adjusted longitudinally uponthe flange, 10, and thereby any wear between the dove-tail rib, 8, and its race or runway may be compensated for, or taken. up.

As before stated the wear plate, 6, forms the bottom of the race or runway for the reciprocable plunger, 7 which is guided and confined to a strictly rectilinear movement partly by the wear plate and partly by the dove-tail rib, 8, and its race or runway. For reciprocating the plunger a link, 14, is jointed to what may appropriately be called its rear end and the other end of this link is jointed to the short arm, 15, of a hand-lever of considerable length, this lever being fulcrumed at the juncture of its tWo arms to a pin, 16, supported by the post, 5*. By this means, by making the longer arm or hand lever, 15 of requisite length the plunger may be operated with any desired force.

The forward end of the plunger carries a cutting blade, 17 which operates in conjunction with a ledger blade in the form of a post, 18, rising from a foot, 19, which is set in a cut-away portion of the wear-plate, 6. This ledger blade, or post, is preferably of semicylindrical shape and its flat diametrieal surface is in the planeor rather a hairs breadth out of the planein which the flat side of the movable blade, 17 travels so that as the movable blade advances there will be a shearing action. In order to still further insure this shearing action the edges of the two blades are disposed at an angle to each other and preferably this is done by disposing the edge of the movable blade, 17, at an angle to its line of move ment, as shown in Fig. I.

For straight Work, 2'. 6., for cutting straight strips into eXact lengths, the machine is providedon one side with a guide, 20, having a vertical wall or flange, 21, which lies in the vertical plane of the cutting edge of the ledger blade, 18, and at right angles to the direction of movement of the movable blade, 17, and on the opposite side of the machine is a stop, 22, carried by a sleeve, 23, adjustably mounted to slide upon a calibrated rod, 24, a thumb screw, 25, being provided for holding the stop in its adjusted position.

One of the principal novel features of the present invention is the ledger-blade in .the form of a post rising at the side of the path traveled by the movable blade. This enables a strip of sheet metal which has al ready been bent to the desired curved or angular shape to be trimmed to proper length, the ledger-blade being practically in the form of an anvil, over which the bent strip can be slipped, and this is not possible with any cutting or trimming machine of which we are aware.

F or illustration, consider a strip of sheet metal that is bent into circular shape and must form a true circle of a certain diameter. If it is too large, by the use of a machine constructed according to the present invention, it is simply necessary to place the ring over the anvil-like or post-like ledger blade, determine how much is to be trimmed ofi, advance the movable blade and the object is accomplished. This is not possible with any existing machine with which We are familiar, all of which operate after the manner of a pair of ordinary shears and are useful only in cutting or trimming sheet metal strips while in the flat.

What we claim as new is:

In a device of-the class described, the combination with a suitable frame and a ledger blade in the form of a post rising therefrom, of a plunger, means for recipro cating it relatively to said ledger blade, said plunger having a longitudinal dove tail rib, said frame having a flange providing in part a guide-way for said dovetail rib, a clamping plate engaging said dove tail rib and means for securing said clamping plate to said flange, the meeting faces of said flange and clamping plate being inclined or beveled whereby they may be adjusted longitudinally relatively to each other and there by take up or compensate for any wear between the dovetail rib aforesaid and its guide-way.

RICHARD HELMOLD. HENRY LORCH.

Witnesses:

LIILIAN F. KINNUOAN, D. M. HorKINs.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of lPatents, Washington, D. Q. 

